58 REPORT OF THE COMMISSIONER OF AGRICULTURE. 



to suffer the same dissociation as at higher temperatures, liberating 

 oxygen and leaving carbonic oxide combined with chlorophyll, and 

 that in this combination it undergoes further reduction under the influ 

 ence of the cell-conteuts, thus entering into the formation of the carbohy 

 drates. Stiitzer, of Gottingen, has tested these views by careful experi- 

 ment under various conditions, and has obtained results which show 

 that the views of Liebig and Eochleder are incorrect, and that oxalic 

 acid can enter into the process of nutrition only after previous oxidation 

 to carbonic acid ; that this being true for oxalic acid, it will also h,old 

 good for the other acids of the carbonyl group ; but tartaric acid and 

 the compounds of the alcohol group may be changed directly into the 

 formative material of the plant. The views of Liebig are also in oppo- 

 sition to the results lately obtained by Mayer. 



Stutzer's experiments with reference to Baeyer's views show that an 

 assimilation of carbon cannot be effected after the manner iodicated, 

 and that we must for the present hold on to the old theory, viz., that of 

 the direct change of carbonic acid to the carbohydrates in the plant con- 

 taining chlorophyll under the influence of light. Whether alcohol may 

 or may not have the function in the plant-nutrition suggested by Stiit- 

 zer, it has at any rate been found in the unfermented juices by Gutzeit, 

 who has succeeded in separating from Eeracleum giganteum, Pasiinica 

 sativa, and Anthriscits cerefolium small quaatities of volatile fluid, which, 

 upon examination, proved to consist of one-third methyl alcohol and 

 two-thirds ethyl alcohol. From examination of fruits in various stages 

 of growth, he concludes that as the prgcess of ripening advances, the 

 ethyl alcohol changes to other compounds, while the methyl alcohol 

 remains constant. This conclusion corresponds to a certain extent with 

 that of Stiitzer, to the effect that the compounds of the methyl or me- 

 thylen groups may change to final products in the plant; but since oxy- 

 gen must first be taken up, these groups are subject to extensive meta- 

 morphoses. The results obtained by Gutzeit, showing a variation in 

 the amount of ethyl alcohol in fruit according to the degree of maturity, 

 are confirmed by those of Lechartier and Bellamy, who have found that 

 when deprived of free oxygen, fruits and leaves give off definit quan- 

 tities of carbonic acid, due to formation of alcohol, according to the stage 

 of ripening; the maximum being reached before complete maturity. 

 With the exception of the horse-chestnut, which gave otf 22 cubic cen- 

 timeters per gram of substance, the limits for fruits and leaves are from 

 to 13.5 cubic centimeters per gram. That this formation of alcohol in 

 fruits, &c., is augmented by absence of oxygen is shown by the results 

 obtained by Missanghi, who observed a formation of alcohol, acetic and 

 formic acids in grapes preserved in an atmosphere of carbonic acid, and 

 showing no indications of decomposition, the flavor of the grapes when 

 taken out being similar to that of fruits preserved iu spirit. l)e Luca's 

 conclusions from his experiments are that saccharine matters of fruits 

 may undergo a change to carbonic acid and alcohol without the presence 

 of alcoholic or acetic ferment. He finds that this change is attended 

 with evolution of nitrogen, and sometimes of hydrogen, and that leaves 

 and flowers act similarly in atmospheres of carbonic acid, hydrogen, or 

 air. Fremy's results lead to totally different conclusions. ' He placed 

 cherries, which had been carefully washed, in hermetically-sealed tubes, 

 under various conditions, and observed, after a time, a liberation of car- 

 bonic acid, with formation of alcohol. On examination with the micro- 

 scope, he found in their interior germs capable of exciting alcoholic fer- 

 mentation in sugar-solutions, and he was therefore led to a belief in the 

 spontaneous generation of this ferment. In this belief he is opposed by 



